Electrospinning construction of heterostructural Co3W3C/CoP nanoparticles embedded in N, P-doped hierarchically porous carbon fibers as excellent multifunctional electrocatalyst for Zn-air batteries and water splitting

Abstract

A series of heterostructural Co 3 W 3 C/CoP nanoparticles embedded in N, P-doped hierarchically porous carbon fibers were fabricated facilely as excellent multifunctional electrocatalysts. The optimal sample CoWCP-NPC-2:1 exhibited highly efficient catalytic activities for HER, OER, ORR, overall water splitting and Zn-air batteries. • The preparing procedure is simple. • The interfacial engineering is employed. • Synergistic effect beween the muti-composition has been shown. • The catalysts show excellent multifunctional performances on ORR, OER and HER. • Broad application prospects in Zn–air batteries and water electrolysis are expected. In this work, facile electrospinning method has been adopted to construct the interfacial engineering heterostructures of Co 3 W 3 C/CoP nanoparticles embedded in N, P-doped hierarchically porous carbon fibers, in which abundant interfaces and multiple active sites were formed. The fabricated catalysts Co 3 W 3 C/CoP/NPC have shown prominent trifunctional electrocatalytic activities for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), evidenced by a positive half-wave potential of 0.803 V for ORR and a much low overpotential (at 10 mA/cm 2 ) of 139/200 mV for HER and OER in alkaline electrolyte, respectively. Furthermore, the rechargeable zinc-air battery based on the optimum CoWCP-NPC-2:1 catalyst has shown a prominent high power density of 205.5 mW/cm 2 and a specific capacity of 800.5 mAh·g −1 after 83.5 h/501 cycles at 10 mA/cm 2 . When the catalyst CoWCP-NPC-2:1 was employed as anode and cathode electrocatalysts for overall water splitting, only 1.49 V of cell voltage was needed to reach 10 mA/cm 2 . This work will provide inspiration for the design of advanced, multifunctional, and performance-oriented heterogeneous catalysts in sustainable energy conversion technology.